In modern society, it is commonplace to distribute digital media files. Digital audio files containing speech have gained increasing popularity and are available for download or online streaming over the Internet. Such speech-containing audio files include so-called audiobooks or talking books, which are recordings of a literary text being read out loud, as well as so-called podcasts, which are episodic series of audio recordings. Digital audio files, like other digital media files, are made available by professional actors, such as media companies, as well as by less professional actors and private individuals. The professional actors have access to advanced equipment and trained personnel that are skilled in the art of editing and producing audio files to provide a good listening experience. To increase the depth of the listening experience, it is not uncommon that professional speech-containing audio files contain background sound, such as music and other environmental sounds. The background sound is thus added to dynamically match the content and context of the spoken language in the audio file.
There is a wide variety of conventional computer programs (“audio editors”) that allow a user to manually edit and master audio files. Some of these conventional audio editors also allow the user to manually select and import background sound. However, even for a professional user, it is a complex and labor-intensive task to add background sound to an audio file. For a non-professional user, it is an even greater challenge to use this type of audio editor, at least to achieve a truly good listening experience.
In essence, a user that wants to add background sound to an audio file using a conventional audio editor need to go through a labor-intensive sequence of steps, such as to listen through the entire audio file, think about what background sound might be appropriate in different parts of the audio file, find or create sound files for the background sound, import the sound files, find the proper location for each sound file in the audio file, select a starting point and an end point for each sound file in the audio file, and select the correct volume of each sound file in relation to speech in the different parts of the audio file.